A variety of packages, including dispensing packages or containers, have been developed for personal care products such as shampoo, lotions, etc., as well as for other materials. Such containers typically have a neck defining an open upper end on which is mounted a dispensing closure. One type of dispensing closure for these kinds of containers typically has a flexible, pressure-openable, self-sealing, slit-type dispensing valve mounted in the closure over the container opening. When the container is squeezed, the valve slits open, and the fluid contents of the container are discharged through the open slits of the valve. The valve automatically closes to shut off fluid flow therethrough upon removal of the increased pressure.
Designs of closures using such valves are illustrated in the U.S. Pat. Nos. 5,409,144, 5,676,289, and 5,033,655. Typically, the closure includes a body mounted on the container neck to hold the valve over the container opening.
A lid can be provided for covering the valve during shipping and when the container is otherwise not in use. See, for example, FIGS. 31-34 of U.S. Pat. No. 5,271,531. Such a lid can be designed to prevent leakage from the valve under certain conditions. The lid can also keep the valve clean and/or protect the valve from damage.
A dispensing closure incorporating such a pressure-openable valve provides advantages not found in other types of dispensing closures. For example, another common type of dispensing closure has a base defining a dispensing orifice which is normally occluded by a closed lid having a plug which enters into, and seals, the orifice. The lid must be lifted open to permit the product to be dispensed through the closure orifice. The lid must be manually closed after dispensing the product in order to permit the container to be carried or moved in any position other than a non-vertical position. Further, the lid must be closed in order to minimize evaporation or drying out of the product within the container. Also, the lid must be closed in order to prevent contaminant ingress.
Other types of dispensing closures include lift-up spouts or rotatable valve members. These features must be manipulated by the user when it is desired to open a dispensing passage and must be manipulated by the user when it is desired to close the dispensing passage.
With the above-discussed conventional types of dispensing closures that do not incorporate a pressure-openable valve, it may be possible to store the container with the closure thereon in an inverted position (with the dispensing closure at the bottom) so as to maintain the container product near the dispensing passage or orifice. This may be advantageous when the product is a rather viscous liquid because, when the inverted dispensing closure is opened, the product is already located at the dispensing passage or orifice and the dispensing time is minimized.
However, while the inverted storage of such a dispensing closure and container may speed dispensing of a viscous product, this can result in creating a rather messy condition at or around the dispensing closure passage or orifice. For example, with conventional dispensing closures that have a lid plug sealingly occluding a dispensing orifice in a closure base, inverted storage causes the inner end of the lid plug to be coated with the product. When the lid is opened, the product on the end of the plug is carried with the plug along the surface of the orifice. Some of the product sticks to the surface of the orifice and/or adjacent exterior edges of the closure base around the orifice. Some of the product also sticks to the lid plug. When the lid is subsequently closed after dispensing the product, the product on the lid plug and around the closure base orifice can create a messy condition around the exterior edge of the dispensing orifice. With the dispensing closure in the closed condition, the product around the exterior of the dispensing orifice can dry out and become somewhat hardened or encrusted during a subsequent period of non-use. This is not only aesthetically unpleasant, but it can inhibit the easy opening of the lid during subsequent use.
A pressure-openable dispensing valve advantageously eliminates or minimizes some of the above-discussed problems. Because such a valve does not have to be directly manipulated to effect its opening or closing, the user merely needs to squeeze the container to effect dispensing of the container product. Although such a simple squeezing action is generally required for dispensing a product, especially a viscous product, through any type of dispensing closure, the use of a pressure-openable valve in a dispensing closure eliminates the need to also initially, manually manipulate the valve, spout, or lid employed with other types of conventional closures.
Because a closure with a pressure-openable dispensing valve remains closed unless the container is squeezed, the closure and container can be inverted for storage (with the dispensing closure and valve at the bottom). Product does not leak through such a valve, and there is little or no mess on the exterior of the valve or surrounding closure surfaces.
Further, the use of a pressure-openable valve permits more accurate control of the dispensing process. Because the pressure-openable valve typically has a relatively thin membrane in which the dispensing slots are defined, there is no long orifice or passage through which the product must pass prior to discharge from the dispensing closure. Thus, the product discharges from the dispensing closure through such a pressure-openable valve relatively quickly and in substantially direct response to squeezing forces applied to the container which are readily sensed by the user as the user squeezes the container. The user has a more accurate "feel" of the relationship between the container squeezing force and the discharging product as the user squeezes the container.
Further, because the pressure-openable valve membrane defining the dispensing aperture slits is relatively thin, and because the valve can be positioned in the dispensing closure at, or very near, the most exterior surface of the closure, the user can readily observe the valve and its dispensing slits. Thus, the user can easily see the product being discharged, and the user can more readily determine how hard to squeeze the container and when to terminate the squeezing of the container.
While dispensing closures with pressure-openable dispensing valves function generally satisfactorily in applications for which they are designed, it would be desirable to provide an improved dispensing system incorporating such pressure-openable valves. For example, in conventional dispensing closures incorporating such pressure-openable valves, special retention systems are required to hold the valves within the closures. In particular, a pressure-openable valve typically is retained in the closure base by means of a separate retainer ring which is snap-fit into the closure base over a flange of the valve. Thus, at least three separate components are typically required in such a conventional dispensing closure: the closure base (which may or may not include an auxiliary, hinged lid), the pressure-openable valve, and the retainer ring.
Such snap-fit rings are small and somewhat flexible. Because the pressure-openable valve and the retainer ring are both relatively small, it is difficult to provide a design which facilitates component assembly and proper snap-fit retention. Careful control of dimensional tolerances is required in order to insure that the components can be properly assembled and in order to insure proper engagement of the snap-fit retention features.
During the manufacture of such a dispensing closure, processes must be employed to manufacture, handle, and assemble (1) the relatively small, and very flexible, pressure-openable valve, (2) the small, snap-fit retainer ring, and (3) the closure base. The manufacturing processes include the following: the manufacture of the three components, the temporary storage of the three components, the processing of the three components (including quality control inspections and material handling (including conveying)), and the assembly of the components.
The above-discussed manufacturing processes are susceptible to problems. For example, the components can be inadvertently damaged during the manufacturing operations. The components can also be inadvertently misaligned during assembly (e.g., resulting in an ineffective, or loose, snap-fit retention of the valve within the closure base). This can more easily occur if the valve is molded from liquid silicone rubber which is soft and pliable. Such a material is preferred in some types of packaging, and has proven particularly advantageous since the material is inherently relatively inert, and will therefore not either adulterate or react with most products contained within a container. Examples of a commercially available valve molded from silicone rubber are disclosed in the above-identified U.S. Pat. Nos. 5,409,144, 5,439,143, and 5,676,289, and these patents are incorporated herein by reference thereto.
Although liquid silicone rubber possesses many attributes for use in packaging, it also has other characteristics which render such applications problematic. For example, the surfaces of silicone rubber components are extremely tacky or sticky, having a very high coefficient of friction. As a result, the proper handling of such components is difficult. For example, in attempting to attach a silicone rubber dispensing valve to a container by a conventional snap-fit retainer ring or threaded collar arrangement, the surfaces of the valve flange may stick to the adjacent surfaces of the container and a retainer ring or threaded collar before the ring or collar can be mounted securely enough to create a leak-resistant seal. Tightening of the threaded collar often causes the valve flange, as well as the entire valve, to distort from its designed shape, thereby preventing the formation of a secure seal, and/or changing the intended dispensing and sealing characteristics of the valve.
Thus, the manufacturing processes--involving separate molding of three or more components, inspection, handling, and assembly--must be undertaken with great care which is difficult and expensive to provide. Notwithstanding the exercise of a high degree of care in the manufacturing processes, such processes remain a potential source of trouble and can occasionally result in the manufacture of a defective assembly.
Further, the multi-component dispensing closure employing a pressure-openable valve is prone to failure after manufacture when subjected to intentionally or inadvertently applied high impact loads. For example, when a completed multi-component closure is shipped to a packager for mounting on a filled container, the packager typically handles the closure with automatic equipment. A portion of the closure may be snagged by such equipment, or the closure may be pushed with excessive force against another object. These actions may lead to a loosening or separation of the closure assembly components prior to, or during, the mounting of the closure on the filled container. This can create problems in the packager's automated filling line and lead to spills and/or shutdowns of the line while the problem is corrected.
In addition, when the completed package (comprising the filled container and multi-component dispensing closure mounted thereon) is put into the distribution channels by the packager, accidental or intentional loads imposed on the closure may cause a failure of a part of the closure. If the package is subjected to excessive impact forces during shipping and/or while being stored and/or displayed, then damage (e.g., loosening) of the closure components may occur.
Also, the fact that the conventional closure includes an assembly of the three components (closure body, valve, and retention ring or collar) makes it easier for someone to tamper with the closure by partially or completely separating the closure components. Accordingly, it would be desirable to provide an improved dispensing system which would eliminate, or at least minimize, the problems associated with multi-component dispensing closures.
It would also be desirable to provide an improved dispensing system for a package which would reduce the number of separate components needed to produce a completed package.
It would also be beneficial if such an improved dispensing system could accommodate the use of a variety of different materials.
Further, it would be desirable if such an improved dispensing system could be provided with a design that would accommodate efficient, high quality, large volume manufacturing techniques with a reduced product reject rate.
The present invention provides an improved dispensing system which can accommodate designs having the above-discussed benefits and features.